Summary of High Brightness Beams Workshop Erice 2005 G. A. Krafft - PowerPoint PPT Presentation

ERLs in High Energy and Nuclear Physics in High Energy and Nuclear Physics ERLs Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

Electron Cooling Electron Cooling Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

ERL- -Based Electron Cooler Based Electron Cooler ERL RHIC electron cooler is based on a 200 mA, 55 MeV ERL 20 nC per bunch, 9.4 MHz Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

BNL ERL R&D Facility BNL ERL R&D Facility e - 15-20 MeV Phase adjustment chicane Controls & Diagnostics Magnets, vacuum Cryo-module Vacuum system SC RF Gun e - 4-5MeV e - Beam dump Laser 4-5 MeV SRF cavity 1 MW 700 MHz Klystron 50 kW 700 MHz system Klystron PS Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

ERL Under construction Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

Cryomodule Design HOM ferrite Space frame Tuner location 2K main line 4” RF shielded assembly support structure gate valve Cavity assembly Vacuum vessel Vacuum vessel 2K fill line Outer magnetic shield He vessel Thermal shield Fundamental Power Coupler assembly Inner magnetic shield Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

Superconducting RF gun under development 703.75 MHz gun. 2x0.5 MW input couplers. HOM damping thru beam tube. Various cathode schemes, including encapsulated cathode behind diamond window – isolation cathode ↔ gun. CW performance 0.5 ampere @ 2 MeV. Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

Two Proposed Electron- -Ion Colliders Ion Colliders Two Proposed Electron ELIC eRHIC Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

eRHIC eRHIC Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

ELIC Design ELIC Design Ion Linac and pre-booster Ion Linac and pre-booster Ion Linac and pre-booster n g o n C o o l i E l e c t r IR IR IR IR IR IR Snake Snake Snake Solenoid Solenoid Solenoid 3-7 GeV electrons 3-7 GeV electrons 3-7 GeV electrons 30-150 GeV light ions 30- 150 GeV light ions 30- 150 GeV light ions Electron Injector CEBAF with Energy Recovery CEBAF with Energy Recovery CEBAF with Energy Recovery Beam Dump Beam Dump Beam Dump Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

Circulator Ring Circulator Ring 1/f c C CR /c ~100 C CR /c J f f Injector t J Circulator Ring t Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

Summary Summary � ERLs provide a powerful and elegant paradigm for high average power free electron lasers. � The pioneering ERL FELs have established the fundamental principles of ERLs. � The multitude of ERL projects and proposals worldwide promises an exciting next decade as: . Three currently operating ERL-FELs will reach higher performance . At least five more ERLs are in serious planning stages and will likely be constructed . New advanced concepts are being explored; most of the applications need high average brightness beams Erice 2005 HBB Workshop 11 October 2005 Operated by the Southeastern Universities Research Association for the U. S. Department of Energy Thomas Jefferson National Accelerator Facility

Needle cathodes for high-brightness beams Chase Boulware Jonathan Jarvis Heather Andrews Charlie Brau

Outline of the talk • What is brightness? – Definition – Sources • Why is brightness important? – Light sources – FELs • How do we get high brightness? – Photoemission – Field emission – Photofield emission

Definition of brightness • Brightness is • Emittance is – π -1 x area in phase – Density in transverse phase space (old definition) space – Or, weighted – Local property of average over beam beam (rms emittance) 2 1 d I ≡ B N γ β Ω 2 2 d dA I ≈ ( ) π ε 2 2 4 rms N

Electron sources span many orders of magnitude in brightness and current 1.E+19 Brightness (A/m2-steradian) 1.E+18 Nanotubes 1.E+17 Field emission 1.E+16 1.E+15 Needle photo emission 1.E+14 RF photoinjectors 1.E+13 1.E+12 Photo-field emission 1.E+11 1.E+10 Thermionic emission Storage 1.E+09 rings DC photo gun 1.E+08 1.E+07 1.E-07 1.E-05 1.E-03 1.E-01 1.E+01 1.E+03 Current (A)

Why brightness is more important than current • Brightness is a useful figure of merit – Normalized brightness is roughly invariant with respect to beam current, electron energy – Can be used to compare different devices • Often it’s the most important parameter – When brightness is the most important parameter, lower current may be possible – Lower current reduces other problems, including radiation, halo, CSR, space charge

Spectral brilliance of Compton x-rays depends on brightness, not current ( ) / • For small emittance ε << τ + τ γ c N L e πσ γ 2 2 U = spectral brilliance is B T L B ν N τ + τ 2 hqc e L

High electric fields at the surface enhance cathode performance • High electric fields: – Conventional DC guns ~ 10 6 V/m – Conventional RF guns ~ 10 7 - 10 8 V/m – Needle cathodes ~ 10 9 – 10 10 V/m • Enhanced performance due to – Schottky effect on photoemission – Field emission – Photo-field emission – Reduced space-charge effects

Electron emission at the surface of a metal in vacuum occurs by four mechanisms Photoelectric Emission Photoelectric Emission φ Thermionic Emission Thermionic Emission Energy Photo- Photo -field field Emission Emission Fermi Field Emission Field Emission Level Metal | Vacuum

Schottky effect reduces surface barrier at high electric field • Field is enhanced at tip of needle ( ) = E O V R / tip tip ( ) = − 9 10 O 10 10 V/m • Schottky effect lowers barrier at surface ∆ = πε E eE / 4 0 ( ) = 9 O 1 eV @ 10 V/m

Needle cathodes produce high brightness in RF guns* • Field at cathode enhanced by ⎛ ⎞ E L tip = O ⎜ needle ⎟ ⎜ ⎟ E R ⎝ ⎠ 0 tip • Example: – 1 mm diameter, 1 cm long – E 0 = 50 MV/m – E tip = O (500 MV/m) • Space-charge limit ~ 10 8 A/m 2 • Brightness ~ 10 13 A/m 2 -str – before pulse compression! * Lewellen, Sardegna

Conclusions • High brightness is often more important than high current • Needle cathodes operate at high electric fields (10 9 – 10 10 V/m) – Enhanced emission from cathode – Reduced space-charge effects • Interesting physical effects are found at high electric fields – Field-enhanced photoemission (Schottky) – Photo-enhanced field emission (tunneling)

Conclusions • High brightness is often more important than high current • Needle cathodes operate at high electric fields (10 9 – 10 10 V/m) – Enhanced emission from cathode – Reduced space-charge effects • Interesting physical effects are found at high electric fields – Field-enhanced photoemission (Schottky) – Photo-enhanced field emission (tunneling)

Erice A split rf-photoinjector 10 October 2005 Bas van der Geer Marieke de Loos Jom Luiten Marnix van der Wiel Eindhoven University of Technology

Source brightness 2 mc Q ⊥ ≤ B π τ k T A Options (at fixed Q): • Lower Temperature T Ultra Cold Plasma cathode Jom Luiten • Reduce Surface area A Carbon Nanotubes Needle cathodes … • Reduce Pulse duration t Pancake regime

Brightness degradation Gaussian bunch The problem is not the high space charge density ...

Brightness degradation Gaussian bunch ... the real problem is the space charge density distribution . p x x Space charge forces: • Non-linear • Slice-dependent

1989 - 2003 Gaussian bunch Fighting the symptoms: • Emittance compensation (B. Carlsten) • Optimized transverse profile (L. Serafini) • Uniform temporal & radial profile (DESY,...) • ... p x x

2004: Fundamental solution Gaussian bunch Waterbag bunch Space charge forces: p x • Linear • Slice-independent x Space charge forces: • Non-linear • Slice-dependent Thermal-emittance-limited beam!

History of uniformly charged ellipsoids • Uniformly charged ellipsoids: – Have linear fields in all three coordinates O. D. Kellogg, Foundations of Potential Theory (Springer-Verlag, 1929 ). – Only change aspect ratio under gravity self-fields (astrophysics) C.C. Lin et al., Astrophys. J. 142, 1431 ( 1965 ). – Extensively used for modeling purposes in accelerator physics … • Source of inspiration: Transverse laser shaping, short bunches L. Serafini, AIP Conf. Proc. 413, 321 (1997) • Fundamental solution and practical recipe O.J. Luiten, S.B. van der Geer et al, PRL 094802, ( 2004 ). O.J. Luiten, S.B. van der Geer et al, EPAC ( 2004 ).

Waterbag bunch recipe Femtosecond photoexcitation of pancake bunch • ‘half-sphere’ transverse laser intensity profile • Temporal laser profile is irrelevant Automatic evolution into 3-D, uniform ellipsoid Ideal Laser intensity Measured Laser intensity TU/e 2005 Variable ND filter y x radius 0 1 mm

First confirmation from GPT simulations GPT How to Realize Uniform Three-Dimensional Ellipsoidal Electron Bunches O.J. Luiten, S.B. van der Geer et al, PRL 094802, ( 2004 ).

Split rf-photoinjector Waterbag bunches, 100 MV/m, 3 GHz, 10 MW p z p z p z z z z fs laser solenoids ½ cell 2 cell booster / compressor 1.2 MeV 3.5 MeV 0.4 m 1.1 m ?

Modeling issues Tracking with GPT: • High-resolution field-maps, no truncated power series • No envelope / paraxial assumptions • 3D space-charge with image charges on cathode Cavities: • E z (z,r) is a function of r! • SF field-maps Solenoids: • Analytical expressions Axial incoupling: DESY • Final design: SF-Fields Elliptical irises: Strathclyde

RF-cavities 3 GHz, 100 MV/m • Axial incoupling (DESY) • Elliptical irises (strathclyde) 40 40 Circular Elliptical 30 30 R [mm] R [mm] 20 20 10 10 0 0 50 60 70 80 90 100 60 70 80 90 100 110 z [mm] z [mm] GPT GPT • µm precise design (Marieke de Loos) 2.625 Fred Kiewiet (Eindhoven) 2.5 Terry Garvey (LAL) / Dino Jaroszynski (Strathclyde) 2.6 Seth Brussaard (Eindhoven) 1.5 Jom Luiten (Eindhoven)

Optimize for 6D brightness 2000 RMS spot-size [micron] 1000 500 200 140 µm rms spot size 100 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 z [m] GPT 800 0.010 700 A 600 0.005 Current [A] vx/c 400 0.000 100 fs FWHM -0.005 200 ε = 0.7 µm -0.010 0 -100 -50 0 50 100 -0.4 -0.2 0.0 0.2 0.4 z [micron] x [mm] GPT GPT

Conclusion: Reached our goal • Develop compact high-brightness rf-photogun – Using waterbag concept – Established 100 MV/m S-band technology • Parameters Reached – Peak current: 700 A – Emittance: 0.7 µm 1.4 kA/µm 2 – Energy: 3.5 MeV – Pulse length: 120 fs rms – Spot size: 140 µm rms – Energy spread: 40 keV rms

Observation of Ultra-Wide Bandwidth SASE FEL Gerard Andonian Particle Beam Physics Laboratory University of California Los Angeles The Physics and Applications of High Brightness Electron Beams Erice, Sicily, October 9-14, 2005

Collaboration • UCLA – G. Andonian, A. Murokh, C. Pellegrini, S. Reiche, J. Rosenzweig, G. Travish • BNL-ATF – M. Babzien, I. Ben-Zvi, J. Huang, V. Litvinenko, V. Yakimenko • INFN-LNF – M. Ferrario, L. Palumbo, C. Vicario

Outline • Experiment Description • VISA I Summary • VISA IB Experiment – Results – Analysis (Start-to-end) – Double Differential Spectrometer • VISA II • Seeded Amplifier Experiment • Conclusions

Motivation • Proposed Scheme for ultra short pulses – Energy chirped e-beam � FEL � freq. chirped radiation • Explore Limits of SASE FEL with energy chirped e-beam • Develop advanced beam manipulation techniques & measurements Freq. chirped radiation output Energy chirped e-beam δγ δω δγ l l γ = α γ = α 2 2 ฀ ω L L b b

Experiment Layout • Accelerator Test Facility (ATF) at BNL – Host for VISA I & II – 70 MeV beam – 28 m beam transport • 20 deg bend (F-line) • Undulator – 4 x 1m sections – FODO lattice superimposed (25 cm period) –strong focusing VISA Undulator Parameters – External steering coils (8) Undulator type Planar – Intra-undulator diagnostics (NdFeB) • 50 cm apart Number of periods (N u ) 220 • double-sided silicon • SASE FEL Peak field (B pk ) .75 T • e-beam (OTR) Undulator Period ( λ u ) 1.8 cm Gap (g) 6 mm Undulator Parameter (K) 1.26

VISA I Summary • Results Gain ~ 10 8 due to nonlinear compression in – dog-leg (F-line) – Shortest gain length recorded in NIR (~ 18 cm) – Higher order angular spectra – CTR & Higher Harmonic Gain • Start to End Simulation Suite – UCLA Parmela – Elegant VISA I Gain Curve – Genesis • Codes Benchmarked to measurements – Post linac, post-dogleg, FEL 6 mrad 6 mrad Far-field radiation pattern (angular spectrum): measured (left), simulation (right)

VISA IB: Experiment • High gain FEL – Chirped beam amplification SASE energy ~2 µ J – – close to saturation • Up to 15% bandwidth observed • Very reproducible and unusually stable – insensitive to RF drifts and phase jitter • Characteristic double-spike structure Wavelength Spectrum of FEL at VISA measured with Ocean Optics USB2000 Spectrometer.

VISA IB: Experiment • High energy slits (HES) • adjustable collimator • Controls beam size in F-line • FEL stability • same fraction of beam propagates through HES, regardless of centroid jitter e-beam at HES a) fully closed slits (500 pC, 2.8% chirp) • Compression b) fully open slits (60 % Transmission, 330pC) • monitored by Golay cell • measures CTR • CTR peaked when p 0 set to optimize compression • Current ~ 300A • Compression stronger • higher degree of chirp

VISA IB: Analysis • Start-to-End – Experimental Spectrum features reproduced – Angles Important • Off-axis Doppler Shift λ ⎛ ⎞ 1 FEL output Spectrum reproduced by ( ) 2 λ = + 2 + γθ u 1 K ⎜ ⎟ r γ 2 2 ⎝ 2 ⎠ Genesis (~11% bandwidth)

VISA IB: Analysis • Linear chirp applied at linac • High Current • Compression in dogleg – I ~ 300 A – Portion of beam is always in “correct” comp. regime – Better than VISA I – Collimation ~40% (300 pC) – Benchmarked to data taken in F-line • Leads to off-axis injection of compressed core

Double Differential Spectrum • Double Differential Spectrum (DDS) 2 d I – Unfolds correlation between ω Ω d d angle (slits) and frequency (gratings) – Preliminary setup • improvements coming • calibration lamp • graduated slits Genesis Simulation of DDS for VISA IB Double differential spectrum: Experimental Setup running conditions ω ω θ •DDS measurement at VISA . •Doppler Pattern observed •Higher bandwidth – complex forms θ •Rich spectral structures

VISA II • Energy chirp SASE FEL operation – linearize transport • Sextupole correction in F-line • Running Conditions – Back of crest acceleration – Negative R 56 compression – 70% Transmission • Start-to-end Simulations – High Current – Low Emittance Longitudinal Phase Space for VISA II Case – High gain FEL post linac (above) and pre-undulator (below). • Frequency chirped radiation • Modified FROG

Compression Studies at the ATF with the UCLA-BNL Chicane Gerard Andonian Particle Beam Physics Laboratory University of California Los Angeles The Physics and Applications of High Brightness Electron Beams Erice, Sicily October 9-14, 2005

Outline • Motivation • Technical Specifications • Coherent Transition Radiation (CTR) – Recent Data • Coherent Edge Radiation (CER) – Theory overview – Simulations – Preliminary Results • Outlook

Motivation • Generation of compressed sub-micron beams – Study radiative effects (CSR, CER) emitted from short beams – Continue UCLA Neptune compressor physics studies in acceleration field dominated regime (space charge -> coherent radiation) – May greatly impact performance of future compressors and FELs (e.g. microbunching instability) – Use CER as non-destructive bunch length monitor Parmela-Elegant simulation longitudinal phase space of beam, with compression from 50A to 1.5 kA.

Compressor • Designed and Constructed at UCLA – Modeled with Amperes – Engineering + safety concerns addressed by ATF • Installed and operational at ATF – Add to ATF core capabilities Compress from 350 µ m – 20 µ m – • Extensive Simulation work – TREDI, Field-Eye, Parmela, Elegant

CTR Measurement • Michelson Interferometer – Commercial Product – Compact Footprint – Convenient Alignment Resolution : 10 µ m – 1.5 mm (rms) – • Observe CTR from insertable foil – Golay Cell detectors – Autocorrelation • UCLA time-domain methods (fitting) and data acquisition

CTR Data • Recent CTR data g – Beam core compression not strongly dependent on phase 1000 • UCLA Fitting technique σ = 27 µ m (rms) • • Use double Gaussian 900 – Reproduces expected pulse shape (ramped with tail) 800 700 600 - H x - d L - H x - d L - H x - d L 100 200 300 400 C0 + C1Exp A 4 s 2 E + C2Exp A E + C3Exp A E 4 H s 2 + z 2 L 4 H s 2 + 2 z 2 L 1.2 2 2 2 1 -17 deg 0.8 1000 -20 deg -23 deg 0.6 -26 deg 500 -29 deg I s ( ) Ip ⋅ 0.4 -32 deg ⋅ I1 s ( ) Ip 0 0.2 500 1500 1000 500 0 500 1000 0 s 0 50 100 150 200 250 300 350 400

CER Experiment • Radiation collected from boundary region of dipoles 3-4 – 7 m transport • New regime for Edge Radiation – <50 micron wavelength • Cold Bolometer – 4.2 K Si bolometer (IR Labs)

CER Overview • Comparison to CSR – Not well distinguished from CSR • CER calculations at short wavelengths – Modeling with : – Like CTR at long wavelengths • Semi-analytical – Radial polarization • Field-Eye CER CSR Chubard, Smolyakov, J. Optics 24 (1993) 117

CER Results • CTR+CER as a function of rf phase – Max signal -19 deg off crest • 11 deg forward of min momentum spread 0.8 • Polarizer Polarizer Signal / – Radial polarization 0.6 Full Signal • Filters – Reconstruct spectrum 0.4 0.2 0 0 45 90 135 180 Polarizer Angle (deg)

Momentum Spread • Observation of bifurcation – Momentum spectrum • Strong breakup of momentum distribution at phase of full compression • Currently being studied with TREDI code Image of beam in spectrometer (horizontal is bend plane). Min. energy spread and no compression - 9 deg fwd of crest (left); Max. compression -19 deg fwd of crest (right).

Conclusions • Summary – Chicane compressor installed and commissioned – Compressor provides a rich data set • CTR, CER, momentum spread, tomography – Simulations need to catch up • Microscopic physics model • Future Run Plans – CER filter measurements – Improved CER polarizer measurements – Compare to models (Field-Eye)

October 11, 2005 ICFA Workshop on The Physics and Applications of High Brightness Beams “ High Brightness Beam Applications: Inverse Compton Scattering ” Nuclear Professional School University of Tokyo Mitsuru Uesaka

Monochromatic Tunable Hard X-ray Source by X-band-linac/YAG-laser Compton Scattering Dynamic image <3m of coronary artery Laser system Laser circulation system X-band Klystron X-band accelerating (decelerating) structure Monochromatic hard X-ray Intravenous injection X-band power supply of contrast agent Patient Total Cross Section of X-ray Moving stage(bed) attenuation 10 7 Total Cross section[b/atom] for various elements 10 6 2D X-ray detector 10 5 Moving arm 10 4 K 1s: 33.169 keV Iodine (Z=53) 10 3 <5 m Gives high contrast 10 2 Scale of system: less than 5m x 5m(with the power supply) 10 Carbon (Z=12) Price: ~4 million dollars Oxygen (Z=16) 1 X-ray energy(max.): 10~50 keV Hydrogen(Z=1) -1 10 0 20 40 60 80 100 X-ray intensity: >10 9 photons/s(total) X-ray energy [keV]

Monochromatic Hard X-ray by Compton Scattering laser Collision 0.1 Electron 0.09 X-ray Compton Scattering 0.08 λ 1 0.07 λ = + 2 L ( 1 K ) 0.06 r γ 2 2 2 0.05 3 ] V o h e k / s n o t p 0.04 0.03 （ K : Wiggling angle of electron ） Quasi- 0 1 x [ 0.02 monochromatic a e n g e n g l t r [ r a d ] a c S i λ ≈ µ 0.01 1 m （ laser wavelength ） 00 10 20 30 40 50 60 70 80 90 100 L 5mrad X-ray energy [keV] E n t i b / y r n ( 50 MeV ) γ ≤ 2 10 X-ray energy vs Angle o λ ≤ 1 A （ X-ray ） γ

Pulsed, tunable, monochromatic X-ray machine at MXI Sys./Vanderbilt’s W.M. Keck Free-Electron Laser Facility Machine Specifications: E-beam: 50 Mev Linac running in “single pulse” mode 1 nanocoulomb/pulse Laser: Nd:Glass 1052 nm 20J – (10J compressed to 10 ps) .003 Hz 10 ８ photons/shot X-ray beam: tunable from 12 to 50 keV 1-10% bandwidth

Energy differences in a finger or in a body, such as a mouse 19 keV 29 keV Energy movie from 15 keV to 33 keV We have the ability to specifically tune the X-rays to the imaging task at hand.

Inverse Compton scattering experiment by 70MeV linac and Ti:Sapp laser at PLEIADES, LLNL Alignment Spatial Alignment aluminum cube at collision point Temporal Alignment streak camera Future works Off-Axis Parabola Permanent quadrupole magnet for electron beam focusing � beam size:15 µ m 540 mJ Laser pulse for interaction Tuning up of the UV Laser for photo injector Goal Total flux: 10 8 photons/sec Peak brightness: 10 20 photons/mm 2 /s/mrad 2 /0.1 % band width X-ray image taken by Csl Scintillator Fiber coupling CCD

LOA(France), etc. Hard- X-ray on the Thompson scattering Nuclear Engineering Research Laboratory Graduate School of Engineering University of Tokyo Hard X-rays (~10-20 keV) in a 1-2o cone can be produced with 12TW Laser Electron bunch 50% BS by PIC simulation M Ti:sapphire OAP Laser pulse Gas Jet 50% X-ray OAP 40fs Collision Optical Delay e-Bunch generation Set up for head-on collision Thomson scattering M M Spectrum of x-rays depending on the laser intensity, a 0= eE / mc ω Laser pulse and electron 1.0 1.0 bunch encounter can be 0.8 0.8 a=10 alized Intensity NormalizedIntensity produced with use of a=2 0.6 0.6 the laser self-focusing 0.4 0.4 Norm m ~400 F.He, Y.Lau, D. Umstadter, R.Kowalczyk m ~5 ma x m ax 0.2 0.2 PRL, 90,055002 (2003) 0.0 0.0 0 10 20 30 40 0 1000 2000 3000 4000 A.Zhidkov, J.Koga, A.Sasaki, M.Uesaka ω ~m ω 0 8 γ m m 2 /(1+ a 0 2 ) PRL, 88,185002 (2002) 0

First and Second Generation Inverse Compton Scattering X-ray Sources First Generation MXI Sys/Vandervilt, PLEIADES, U.Tokyo/KEK/JAERI, Sumitomo etc. -Single-electron-single-laser Compton scattering -First demonstration and application -Intensity up to 10^8 photons/s -Intensity fluctuation due to the time-jitter between electron and laser pulse Second Generation U.Tokyo, Lyncean Tech.(R.Ruth), Sumitomo/AIST/KEK, etc. -Multi-scattering of electron- and laser-pulses -Intensity of more than 10^9 photons/s -A variety of applications for medicine, protein structural analysis, nondestructive evaluation and nuclear engineering

Compton scattering hard X-ray source Compact hard X-ray source based on Properties of the generated X-ray Compton Scattering

X-band Linac Facility at Univ.Tokyo Control room RF source Beam line